Production of aralkenyl compounds and polymerization products thereof



Patented Jan. 31 1939 PATENT OFFICE PRODUCTION OF ARALKENYL manor COMPOUNDS POLYMERIZATION PRODUCT8 Heln Israel Waterman and Willem Johannes Gornelis de Kok,

Delft, Netherlands, assignors to =8hell Development Company, San Francisco.

Calif., a corporation of Delaware No Drawing. Application October 26, 1986, Se-

rlal No. 107,825. In the Netherlands November 3 Claims. (01. 260-669) This invention relates to a practical and economicalprocess for the conversion of aralkyl alcohol ethers to useful products of the class consisting .01 aralkenyl compounds 01' the type of 5 styrene and its homologues, and substitution products and polymerization products 01' such aralkenyl compounds.

The process of the invention may be executed in a variety oi suitable manners depending upon the nature of the product or products desired. When the object of the'invention is to convert an arallwl alcohol ether of the classherein described topolymerization products of the era!- kenyl compound resulting from the dealc0hola-' 5 tion or'splitting of a-molecule of an alcohol from a molecule of the treated aralkyl alcohol ether, the process may be executed by contacting the' aralkyl alcoholvether, in either the liquidor the separation of the aralkenyl compound therefrom, be contacted with a polymerization catalyst under conditions of temperature and pressure adequate to polymerize the aralkenyl compound content oi.

the mixture to the required aralkenyl compound polymer. A

35 The aralkyl alcohol ether may be contacted with the dehydration catalyst in the-initial step of the process under such conditionsof temperature and throughput that the alcohol split from the arallml ether is substantially stable. It de- 40 sired, this alcoholmay' be separated from the reaction mixture prior'tocontact'oi the mixture with a polymerization catalyst iorpolymerization of the aralkenyl compounds. "I'hereeovered al-'- cohol. may beus'ed ior'any purpose desired. It

45 may, for example, be utilized lor'the manufacture 01' more oi. the arallwl ether and thus reutilized in the system. Under-some conditions of operation, particularly at relati ely high-tem peratures; the alcohol split from e treated arso alkyl ether m y. under the influ ce oi the dehydration catalyst at the temperature of-the dealcoholation, be wholly or partly dehydrated resulting in the formation of water and the corresponding oleflnic or .substltuted oleflnlc compound. The oleflnic compounds may. or may not 5 be separated from the aralkenyl compound prior to eflectlng polymerization. In the majority of cases it is preferable to treat the reaction mixtureleaving the dehydration zone in its entirety to eflect polymerization of the aralkenyl com- 10,

pounds- The polymerization step may be effected under-such conditions and in the presence of such a polymerization catalyst that. the ar'alkenylcompounds are selectively polymerized; or the poly.- merization may be eilected'under such conditions thatthe oleilne content oLthe mixture'r'vis also polymerized, and a mixture. of olefine polymers as well as aralkenyl compounds is obtained,..or the polymerization maybe effected under such conditions that the aralkenyl, compoundspoly- W merize at least in part with the oleflnes and mixed! or. interpolymers are obtained. ,The ole: fines recovered from the reaction mixture, either prior to or subsequent to the] polymerization treatment, may be separately polymerized .to 5 7 higher molecular weight hydrocarbons useful as motor fuels, components of fuel mixtures, lubricating oils and the like, or. they may be, poly: merized to resins, resinous materials and the like;

orthey may be hydrated to alcohols and/or -ethers, halogenated tovaluable unsaturated halides, converted to halohydrins, etc. v

A specific embodiment of the invention com.-

. prises direct conversion oi the treated aralkyl alcohol ether into polymers of the aralkenyl compound resulting from dealcoholation oi the treat: 1 ed ether by a single stage process which comprises contact of the aralkyl alcohol ether witha solid contact mass consistingof or comprising matei rials capable of effecting substantially simulta- I neously the dealcohola'tion oi the aralkyl'alcohol ether and the polymerization of the 'jaralkenyl compound and other products resulting from the dealcoholation. For this-purpose we mayuse 'a catalyst which under the'conditions of its use the properties, of a dehydration catalyst and a polymerization catalyst, the reactions of dealcoholation and polymerization may be made to occursubstantially simultaneously whereby the desired polymer product may be obtained in a single stage operation.

A principal object of the invention is to provide a practical andeconomical process for the dealcoholation of aralkyl alcohol ethers to the corresponding aralkenyl compounds of the type of styrene and its homologues. The term dealcoholation as used herein and in the appended claims means the splitting out or removal of a molecule of an alcohol from the molecule of the treated aralkyl alcohol ether. compounds prepared in accordance with this embodiment of our inventionare useful for a wide variety of purposes; They may, by any suitablemethod, be polymerized to useful oils, resins and resinous materials; they may be hydrated to valuable aralkyl alcohols and glycols; they may be ,halohydrinated to useful aralkyl halohydrins;

they may be halogenated to saturated and unsaturated aromatic derivativesi they may be carboxylated to valuable aralkyl carboxylic acids; and the like.

If the object is to dealcoholate an aralkyl alcoholether of the class to which the invention pertains to obtain as the main reaction product the corresponding aralkenyl compound of the type of styrene and its homologues, and substitution products of the same, the process is executed by contacting the aralkyl alcohol ether, in the liquid or gaseous phase, with a solid catalyst mass consisting of or comprising a dehydration catalyst capable of effecting substantially onlydehydration at the temperature of operation, the catalyst mass being maintained at a temperature adequate to eifect dealcoholation of the treated ether at a practical rate while undesirable side 'reactions, as polymerization of the resulting aralkenyl compound, are substantially obviated.

The aralkyl alcohol ethers which may be converted to valuable aralkenyl compounds and/or polymerization products thereof in accordance with the process of-the invention may be conveniently represented by the general formula ROR1,wherein R'represents an aralhl radical containing at least two carbon atoms in the alkyl side chain and linked to the ether oxygen atom by a carbon atom of said chain, and R1 represents an alkyl radical or an aralkyl radical different from the aralkyl radical represented by R. The radicals represented by R and R1 may be hydrocarbon radicals or they may 'be hydrocarbon radicals wherein one or more hydrogen .atoms is/are substituted by suitable inorganic sub- -stituents,' such as halogen atoms, an amino group, an o'rwgen atom, ametal radical, the negative radical ofa mineral acid, etc., or an organic substituent as an ether group, a carbonyl group, a. carboxylic acid group, a carboxylic acid ester group and the like. It is seen that R represents aralkyl radicals comprising alkyl radicals as ethyl, propyl; isopropyl, butyl, isobutyl, tertiary butyl, amyl and the like, wherein one or more hydrogen atoms'is/aresubstituted by an arylradical such .as phenyl, cresyl, xylyl, naphthyl, anthryl and the like, which aralkyl radical may be further substituted; The aralkyl radicals represented by R1 may be any one of the above as well as those aralkyl radicals which possess only'a single carbon atom in the side chain as the benzyl radical The. following The aralkenyl phenyl-l propoxy-l ethane, phenyl-l butoxy-l are typical of alkyl radicals which R1 may represent: methyl, ethyl, propyl, isopropyl, butyl, secondary butyl, isobutyl, tertiary butyl, the amyl radicals, the hexyl radicals and the like and their homologues and suitable substitution products.

Twopreferred groups of aralhl alcohol ethers may be represented by the more specific general wherein Ar represents any aryl radical which may be further substituted, Ra, R3 and R4.

representing hydrogen atoms, organic radicals as alkyl, aryl, arallwl, alicyolic, heterocyclic and the like, or inorganic or organic substituents as --Cl,

Br, I, NHz, COOH, COOR, -OR and the like, and X represents an alkyl radical or an aralkyl radical, X containing an .aryl radical different than the aryl radical represented by Ar when R2, R3 and R4 in the second formula represent hydrogen. atoms.

Some readily available aralkyl alcohol ethers which are representative of the class of ethers which are dealcoholated in accordance with the process of the invention are the following: phenyl-l methoxy-2 ethane, phenyl-l ethoxy-2 ethane, phenyl-l isopropoxy-2 ethane, phenyl-l methoxy-l ethane, phenyl-l ethoxy-l ethane,

ethane, phenyl-l methon-l propane, phenyl-l be nzyloxy-2 ethane, phenyl-l benzyloxy-l ethane, phenyl-l benzyloxy-2 propane, phenyI-l methoxy-Z propane, phenyl-l methoxy-3 propane, phenyl-l ethoxy-2 propane, phenyl-2 ethoxy-2 propane, phenyl-l isopropoxy-2 propane, phenyl- 1 methoxy-2 butane, chlor-2 phenyl-l ethoiry-l propane, chlor-3 phenyl-l ethoxy-l propane, dichlor-2,2 phenyl-1 ethoxy-l propane, cresyl-l methoxy-2 ethane,-cresyl-1 methoxy-2 ethane,

cresyl-I ethoxy-l ethane, cresyl-l isopropoxy-l 1 ethane, cresyl-l ethoxy-2 propane, xylyl-l methoxy-l ethane, xylyl-l propoxy-l ethane, naphthyl-l methoxy-l ethane, naphthyl-l ethoxy-l ethane, naphthyl-l ethoxy-2 propane, anthryl-l methoxy-l' ethane, anthryl-l ethoxy-2 propaneandthe like and their homologues, analogues and suitable substitution products.

In the step of our process which comprises dealcoholation of the aralkyl alcohol ether to the corresponding aralkenyl compound, catalysts. of

the class known as dehydration catalystsare preferably employed. In general, catalysts known to be useful for the dehydration of al- 'a sasoi aluminum phosphate, aluminum silicate, the cor-. responding thorium, cerium and zirconium salts, zinc chloride, magnesium chloride and the like. The dehydrationcataiysts may be used severally or in admixture in any desired physical form. If desired, they may be incorporated with or deposited on supporting or "carrier" materials of which the following are typical: charcoal, pumice, clay, iullers earth, diatomaceous earth, bentonite, montmorillonite .and the like. Under some conditions, such carrier materials have dehydratingactivity and maybe used alone. 7 when the process is executed to eifect substantial dealcoholationof the aralkyl ether in the de'alcoholation stage without substantial polymerization of the resulting aralkenyl compound or compounds, the dealcoholation is preferably eiiected at a temperature of from about 200 C. to about 400 0.. in the presence or a catalytic material which eflects substantially only dealcoholation or dehydration under the conditions of operation. A preferred group of dehydration catalysts for this purpose embraces the metal oxides and metal salts above-listed, particularly the oxides and salts or the metals aluminum, thorium, cerium, zirconium, tungsten, chromium, titanium, molybdenum andthe like. It is to be understood that the temperature used will be dealcoholatlon and polymerization are the follow- 'ing: the metalsas zinc, aluminum, copper and pendent to a certain extent on the particular catalyst material selected andupon the particular aralkyl alcohol ether treated. A preferred temperature range is from 200 C. to about 400 C., but higher or lower temperatures may beadvantageously used in some cases. Excellent results have .been obtained by using metal oxide catalysts of the type of alumina, thoria, oeria, etc. at temperatures of from about 250 C. to about 350 C.

The dealcoholation reactionmay be executed with the arallnvl alcohol ether in either the liquid or vapor phase at any desired pressure. Preferably the reaction is eflected in the vapor phase at atmospheric or moderately reduced pressure. In some cases, however, superatmospheric pressures may be advantageously applied.

Suitable representative materials which are capable of catalyzing dehydration and polymeri'zation in the same temperature range, and which may be used in the execution of the invention to convert a'suitable aralkyl alcohol ether directly to polymers of the aralkenyl compound resulting from dealcoholation oi the aralkyl alcohol ether by eflecting substantially simultaneously the demetals of Group VIII of the periodic table, pref erably employed in a finely divided form; the

' acid-acting metal salts as zinc chloride,- zinc bromide, magnesium chloride, aluminum chloride, berylliumchloride, zinc sulphate. aluminums'ulphate, cadmium sulphate, lead sulphate, bismuth owchloride, copper phosphate and the like. The members'ot the above group'of catalysts may be used in admixture with catalysts as herein described which have substantially only a dehydration effect, or they'may'be used with any of the hereinafter described polymerization catalysts .when a stronger polymerization influence is desired. Catalyst masses having a combined dehydration and polymerization action may be prepared by mixing one or more materials which aresubstantially only dehydration catalysts under the conditions of the operation with one or a mixture of polymerization catalysts active under thesame'conditions. ,Other suitable solid catalyst terials as pumice, clays, fullers earth, bentonite The aralkenyl compounds resulting from the dealcoholation of an aralkyl alcohol ether may be polymerized to valuable polymers thereof in a wide variety of manners in either the liquid or .the gaseous phase. The reaction mixture leaving the dealcoholation stage may be conducted directly to a polymerization stage wherein polymerization of the aralkenyl compounds with or in the P esence of other constituents is effected. If des red, the reaction mixture'leaving the dealco holation stage may be first treated and the unikenyl compound separated therefrom and polymerized in the substantial absence of other polymerizable materials or in the presence or with added polymerizable materials,

s The polymerization may be effected in the absence oi catalysts, for example, under the influence of high temperature and pressure, or in the presence of any suitable material capable of catalyzing polymerization of aralkenyl -.com-,

pounds of the type of styrene and its homologues.

When liquid phase methods of polymerization I are employed, preference is given to those polymerization agents, per se or in solution or suspension, which-may also serve as media for the ab sorption or solution of the aralkenyl compounds and other unsaturated compoundspresent. Suitable agents of this type are the mineral acids as the hydrogen halides, the sulphuric acids, the

phosphoric acids, the phosphorous acids, the arsenic acids and the like as well as their anhydrldes. The phosphoric, phosphorous and sulphuric acids may be employed in the liquid state I or in a substantially solid state deposited on or in admixture-with a solid siliceous material or simi-' 'lar absorbent material. The strong organic acids as [benzene sulphonic acid and its homologues and analogues may also be employed. Other suitable polymerization agents which are preferably employed in solution or suspension in water are the acid salts as zinc chloride, zinc sulphate, I

cadmium sulphate, copper phosphate, etc.

Other suitable representative polymerization agents which may be used in liquid or vapor phase operations, but which are particularly suitable for the latter, are the inorganic halides as AlCls, ZnClz, MgCls, FeCla, NiClz, BeClz, BeFz, AsFa, BbFa. SnCls, TlCls, PFs', BF: and the like. Such catalysts may be used alone or in admixture with each other and/or other materials as carriers, metals,

etc. Y ,4

' The polymerization step of the/process may be effected at any suitable temperature and pressure and in the presence or absence of substantially inert diluents and solvents for the reactants and/or products) In general, we prefer to effect the polymerization under atmospheric or superatmospheric pressure since pressure in general favors reactions of this type.

mode of operation described in the example, which is for illustrative purposes only.

" Example A catalyst tube was packed'with granules of alumina (A1203) The packed catalyst tube was heated to and maintained at a temperature of about 325 C. while the vapors of l-phenyl meth-' oxy-l ethane I omieH-o-cm) were passed through it. The product of the reaction was styrene (CoHsCH=CH2), which product was obtained in a yield greater than 80%.

Methyl alcohol was a by-product'o! the reaction;

Substantially the same results were obtained when the aralkyl ethers phenyl-l ethoxy-l ethane and (phenyl-l' ethoxy) -2 propane were treated under like conditions with alumina, as well' as with catalysts as ceria, zirconia, thoria, tungsten oxide, molybdenum oxide and the like.

The many uses to which the products obtained in accordance with the invention may be put have been indicated in the foregoing. The products are highly suitable for the manufacture or polymerization and condensation products such as polystyrene and the like polymers and other resins and resinous materials with glass-like and resinlike properties. Such resins and resinous materials may be mixed with suitable plasticizers and softeners and molded into all sorts of objects,

contingently with the addition oiflllers as saw-'- dust and the like, which-objects can be worked easily with tools such as planes, drills, saws, etc.

fltwillbeapparenttothoseskilledintheartto which the invention pertains that the process of the same may be executed in a batch, intermittent or continuous manner.

' It is to be understood that the terms alkyl radical and aralkyl radical" are intended to embrace, as well as the alkyl and aralkyl hydrocarbon radicals'. such hydrocarbon radicals wherein'one or a plurality of hydrogen atomaislare substituted by suitable inorganic or organic substituents. The term "aralkenyl compound" is intended to embrace compounds of the type oi. styrene as well as substitution products of such compounds.-

The character of the invention and the marked commercial value thereof can be seen from a consideration of the preceding specification and the instance of results given but neither is to be considered as imposing corresponding limitations upon the invention, the scope of which is defined by the appended claims.

We claim as our invention:

1. In a process for the conversion of an aralkyl alkyl ether to an aralkenyl hydrocarbon polymer,

the step which comprises contacting an aralkyl alkyl ether oi. the general formula R-ORi. wherein R is an aralkyl hydrocarbon radical containing at least two carbon atoms in the alkyl chain and linked to the ether oxygen atom by one of said carbon atoms, and R1 is an alkyl hydrocarbon radical, with a solid dehydration-polymerization catalyst mass at a temperature at which simultaneous dealcoholation of the aralkyl alkyl ether and polymerization of the resulting aralkenyl hydrocarbon occur.

2. In a process for the conversion of an aralkyl alkyl ether to an aralkenyl hydrocarbon polymer, the step which comprises contacting an aralkyl alkyl ether of the general formula R-O-Ri, wherein R is an aralkyl hydrocarbon radical containing at leasttwo-carbon atoms in the alkyl chain and linked to the ether oxygen atom by one of said carbon atoms, said R1 is an alkyl hydrocarbon radical, with a .solid dehydrationpolymerizationcatalyst mass at a temperature of. from about 200- C. to about 4 0 0., whereby simultaneous dealcoholation and lymerization occur. and the aralkyl alkyl ether is dealcoholated while the resulting aralkenyl hydrocarbon is polymerized.

3. Ina process for the production oi! a styrene polymer from the alkyl ether of a mono-phenyl substituted ethanol, the step which comprises contacting an aralkyl alkyl ether 01' the general formula R--ORi.'wherein R represents a radicalo! the group consisting oi dealcoholated to styrene while the styrene is being polymerized to a styrene polymer.

HEIN ISRAEL .WA'I'ERMAN. WILLIE 10m CORNELIS DI KOK. 

